After one of his aides emerged two weeks ago as a key witness in the latest ballot-fraud probe in Hialeah, Miami-Dade Commissioner Esteban “Steve” Bovo said he was “deeply disturbed” that his office was “mentioned in the same breath of an absentee ballot investigation.”

But it’s not the first time that a vote-fraud investigation has led to Bovo’s doorstep.

In 2004, in another ballot-fraud probe, detectives focused on a suspected boletero, or ballot-broker, who worked as a staffer for Bovo, at the time a Hialeah city councilman, police records show. The boletero, who was never charged, told investigators that he learned the finer points of ballot collecting from Sergio “El Tio” Robaina — who was arrested earlier this month on vote-fraud charges after a witness said he dropped off ballots at Bovo’s office, court records show.

That 2004 probe, which ended with no arrests, was in many ways a mirror image of the current investigation that has led to two arrests and roiled Miami-Dade’s political scene. That investigation eight years ago exposed many of the ballot-collecting practices facing renewed scrutiny today, and touched many of the same political players — including Bovo.

Bovo says he has never asked his campaign workers to collect ballots — not today, and not when he served on the Hialeah City Council. “I have always instructed my campaign staff to follow state, local and federal election laws,” Bovo said in a written statement.

Records show that four suspected ballot brokers have worked on Bovo’s past campaigns — including Deisy Cabrera, the Hialeah woman arrested last month on ballot-fraud charges.

Bovo said these workers performed other tasks for his campaigns — making phone calls, handing out campaign literature or preparing mailers — but they did not collect ballots for him.

A fifth boletero, Robaina, also helped with Bovo’s 1999 campaign, a longtime Bovo ally said in court papers. But Bovo said Robaina never worked for him.

“Any insinuation that my campaign hired any of the identified people as ‘ballot brokers’ or to do anything in violation of Florida law is just absolutely false,” Bovo said.

But police suspect that Bovo’s Hialeah office was a hub of absentee ballots before the Aug. 14 primary. According to court records, a Bovo aide, Anamary Pedrosa, told detectives that Robaina and other suspected boleteros delivered as many as 164 absentee ballots to Bovo’s Hialeah office — an apparent violation of a county ordinance that makes it a crime to possess more than two absentee ballots of other voters. Pedrosa said she later delivered the ballots to the post office.

Bovo insists that no ballots were collected at his office. He said neither he nor his staff knew what Pedrosa was doing “outside of the commission district office.” Pedrosa resigned from Bovo’s staff on July 27.

Pedrosa also named other suspected boleteros who delivered ballots, including 80-year-old Manuel Lago, who worked on Bovo’s 2011 political campaign, according to sources close to the investigation.

Lago has denied delivering any ballots to Bovo’s office. “No, man, no,” he told The Miami Herald. “I don’t have anything to do with absentee ballots. I tell people, vote for whoever you want, but vote.”